Yes: memory ceiling is huge, WinRM is buggy and unreliable, performance is "variable", totally inconsistent handling of dates and times, being .Net it's UTF-16 internally so streams are painful to work with, escape characters argh, variable scoping is horrible, most of the API you have to hit to get stuff done is wrapping ancient bits of weird win32 and DCOM and WMI thus has inconsistent error handling and ability to actually do what it is told.
While powershell has gotten a lot faster in the most recent versions its still pretty slow for anything involving computation; most of the type my equivalent python code beats the pants off of it.
The expressiveness is nice, but oftentimes modules won't support it or require weird ways of using the data to get the performance you want (mostly by dropping out of the pipe.)
The choices around Format- vs Out- vs Convert- are Very Confusing for new people and the "object in a shell but also text sometimes" way of displaying things is weird and until recently things like -NoTypeInformation or managing encoding in files was just pointlessly weird.
The module support and package management is still entirely in the stone ages and I regularly see people patching in C# in strings to get the behavior they want.
"Larger" modules tend to get Really Slow - the azure modules especially are just an example of how not to do it.
The way it automatically unwraps collections is cool, but gets weird when you have a 1 vs many option for your output, and you might find yourself defensively casting things to lists or w/e.
The typing system in general is nice to get started on but declaring a type does not fix it, so assignment can just break your entire world.
There's still a lot to love about the language when you are getting things done in a windows environment its great to glue together the various pieces of the system but I find the code "breaks" more often than equivalent python code.
My philosophy about any shell language is that if performance is a concern, then you should probably use a real programming language for it. Using shell scripting to handle batch processing tasks just creates dependencies on unmaintainable code.
If performance is too bad, you can only use the shell for toy examples, which means there's no reason to have a real shell at all and you might as well go back to COMMAND.COM or equivalent. It's taking the idea of Unix-style scriptable shells and Improving the implementation to the point of unusability.
It's also inhibited by typical corporate crapware, but with a pretty barebones/vanilla config, in PowerShell takes a full four to ten seconds just to open a new session on my work computer.
PowerShell isn't even fast enough for basic interactive usage, never mind batch processing.
Simple tools with simple rules will outlast most of the code we'll all build.
Picking things like grep, awk, and sed means your knowledge will be widely applicable going forward, and many people caring about their performance both backwards and forwards in time means your shell can be pretty fast.
Unfortunately after working with it for a few years I utterly despise PowerShell for many other reasons.